Kikuchi-Fujimoto Disease With Unusual Cutaneous Findings.

Area of Science:

• Dermatology
• Pathology
• Pediatrics

Background:

• Kikuchi-Fujimoto disease (KFD) is a rare, self-limiting disorder characterized by lymphadenopathy and constitutional symptoms.
• KFD typically affects young adults, with pediatric cases being less common.
• The etiology of KFD remains unclear, though viral and autoimmune factors are implicated.

Observation:

• A 14-year-old patient presented with fever, weight loss, and pancytopenia, initially suggestive of various systemic illnesses.
• Physical examination revealed tender subcutaneous nodules and cervical lymphadenopathy, prompting further investigation.
• Histopathological analysis of lymph node biopsy confirmed KFD, while skin biopsy revealed unique findings.

Findings:

• The lymph node biopsy demonstrated characteristic features of Kikuchi-Fujimoto disease.
• Skin biopsy revealed mild superficial dermal edema with a neutrophil-predominant inflammatory infiltrate.
• Notably, rare atypical monocytoid cells were observed in the skin biopsy, presenting a Sweet-like morphology previously unreported in KFD.

Implications:

• This case highlights a novel histological finding (Sweet-like morphology) in the skin biopsy of a pediatric patient with KFD.
• The presence of Sweet-like morphology necessitates consideration of Sweet syndrome in the differential diagnosis of KFD with cutaneous manifestations.
• Further research is warranted to understand the significance and potential mechanisms underlying this association.